Reactor Shutdown Darkens South Florida 356
grassy_knoll asks, "So how fragile is the electrical grid, and just what technical problems could shut down five reactors?" "Five reactors at a nuclear power plant in Florida had gone down on Tuesday and two were now back online amid a massive power outage in the southern state, CNN reported. The report on the Turkey Point nuclear plant came as four million people had lost electricity in Miami and elsewhere in Florida, with traffic signals out and major delays on roads, authorities and media said."
D'oh (Score:4, Funny)
Nothing to see here... (Score:2)
I wonder what Dave Barry will write about this one?
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Well, crap... (Score:4, Funny)
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http://en.wikipedia.org/wiki/Springfield,_Florida [wikipedia.org]
(Simpsons Joke)
(my head)
Re:Well, crap... (Score:4, Funny)
Some background information. (Score:5, Informative)
Soon things will look like a Mad Max movie. (Score:5, Funny)
Oh, great.... (Score:2, Funny)
5 reactors? (Score:5, Informative)
Re:5 reactors? (Score:5, Funny)
MOD PARENT UP (Score:2)
Re:5 reactors? (Score:5, Insightful)
Nuclear plants however are only available in the huge, bulky variation. In fact they come from some technological stone-age where the idea of giant-gigawatt-city-plants was considered the best solution imaginable.
Nowadays one tries to break power generation up into much smaller parts - perhaps as far as to your own cellar. This would have in fact many advantages besides reliability, "combined heat and power" comes to mind.
Re:5 reactors? (Score:5, Insightful)
Of course, one can have various definitions of "huge" (insert Viagra jokes here), but the US Navy might not agree with you.
But I really don't think it's a good idea for everyone to have a nuclear reactor in their cellar. Most folks don't have the technologic where-with-all to keep their PC's or cars running correctly. Until and unless you can get any power generation technology simple enough that it rivals a toaster in complexity, I will take centralized facilities any day.
"Mommy! Why is the basement glowing?.
Re:5 reactors? (Score:4, Insightful)
Re:5 reactors? (Score:5, Insightful)
For nuclear, the economics of initial construction and design requirements make much more sense to do huge reactors. A reactor has to have huge amounts of shielding for protection in case of mishap (it's mostly not for the regular reaction from the core). We're talking shells of concrete several feet thick. And steel too. It's cheaper the larger your volume/power ratio and such is.
None of the reactors listed here [doe.gov] are below 1 MW of electric power.
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Don't forget about distribution and conversion losses.
Re:5 reactors? (Score:4, Informative)
BTW, there are very small reactors that are designed for something like a small town in Alaska and also ones for ships.
And the reason there are a lot of small plants in the last 20 years or so is that the rate of electricity demand is growing slowly and large plants that won't be fully needed for several years weren't as profitable as something smaller albeit less efficient.
However, that is changing as many companies want to replace groups of smaller plants with a large ones. That and the 'why have anything else' natural gas power plants of the nineties now operate often at a lost and are run only when needed. And the reactors are only getting bigger, not because people still think in the stone age, but because that is what they are being called for. France wants all the power it can get per reactor, they just sell the excess to Germany who is having issues with a stable power grid. South Africa wants 23 gigawatts, China wants 50 gigawatts, Texas 15, UK 20, etc. And they are willing to pay for it, because over its lifespan there are very very few plants that aren't profitable at any scale and many much more profitable than originally thought, look at entrgy and exelon profits in the last few quarters.
And a large system of many small plants are have great reliability in terms of having some power, but are very poor at consistent power. Germany and Denmark are good examples of nations with many small plants and they depend heavily on other nations power systems as a back up.
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Or the technological stone age where scaling up the volume you use to generate electricity cuts down on the ratio of volume to surface area, where you lose heat and efficiency.
Good thing we've gotten around that old Length^3 = volume = power production and Length^2 = area = ambient losses stone age philosophy.
Sarcasm about thermal efficiency aside, the added expense th
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Thermodynamics is like that, stone age or not. Thermal power scales up giving you more than double the power for twice the size.
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You really think a tiny little turbine is going to be as efficient as a huge one in a powerplant?
Yes, I do.
Of course the great turbine in the power plant is more efficient as my tiny little local one, but the power from the large, centralised and thereby far-off power plant has to come to me first. The biggest consumer on the net is the net itself. Most of the power is just lost traveling to my home!
But that's not even the worst part: what about all the heat? In a big power plant it is usually just blown in the air (or at most used locally). With village-sized plant most of it could be harnessed.
Ok, i
Reactors shut down because nowhere to send power (Score:5, Informative)
It was not, as some posters seem to have misread even the summary, that the reactors went down first and caused the outage. Mind, once the reactors are down it takes longer to bring the whole grid back up, so in that sense it's contributory.
Re:Reactors shut down because nowhere to send powe (Score:4, Informative)
And now, we return you to regular scheduled blackout... if this were an actual emergency, you would of killed the person sitting next to you.
Tes
Re:Reactors shut down because nowhere to send powe (Score:4, Informative)
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Yes, and still they fail. We had a somwhat interesting event at one of our sites in Sweden, Forsmark [wikipedia.org]: When a fault in the outbound net triggered a shutdown in a similiar way, a power spike at the internal system forced all of the backup generators down, stopping power to the pumps. Fortunately, they were able to be restarted manually.
There is some debate about whether we had a risk of meltdown (our reactors *do* have some shielding if that would happend), but still the lack of safety culture was heavily
Re:Reactors shut down because nowhere to send powe (Score:5, Informative)
Ah, the usual problem. (Score:3, Interesting)
I guess this is bound to crop up in CSI Miami... (Score:5, Funny)
And what did nuclear have to do with it? (Score:5, Insightful)
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Re:And what did nuclear have to do with it? (Score:5, Interesting)
Re:And what did nuclear have to do with it? (Score:5, Informative)
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Its a good thing (Score:4, Insightful)
Bad editorializing. (Score:3, Insightful)
just what technical problems could shut down five reactors?
If the article submitter had actually read the article, he might have noted the nuclear plants shut down because of an under voltage in the rest of the system (caused by a breakdown elsewhere). My guess is this is some kind of safety measure, otherwise why would you have the system shut down?
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http://www.nrc.gov/reading-rm/doc-collections/news/2008/08-037.html [nrc.gov]
Re:Bad editorializing. (Score:5, Funny)
Perhaps people should 2 seconds of research before they begin jumping to conclusions about things.
You're obviously new here...
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andnothingofvaluewaslost (Score:3, Insightful)
Time for this Asia (China) resident to get his own back by tagging this story as 'andnothingofvaluewaslost'.
For those of you who don't know, a lot of the stories about Asian countries losing connectivity to large parts of the rest of the world were tagged as 'andnothingofvaluewas lost'. Of course, it could be argued that it is the countries that lost the connectivity that didn't lose anything of value, but hey.
I wonder why it is often stated that such places have lost their 'connection to the internet' when at least some of them probably don't much notice (China wouldn't notice much more than MSN not working, for example) - do people think that 'the internet' lives in the USA or something?
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At any rate, I also think the tagging system is garbage. I think the best fix would be to let the submitters specify the article tags. Yes, give me the POWER! I mean us! Us the article submitters!
Glad they got things back up (Score:2, Insightful)
On a side note:
I really hate how every problem requires a clarification that it wasn't Terrorists.
We live in a state of fear, and not a state of freedom. Are there people that really freak out and cry "Terrorists!" when something goes wrong these days. I'm not complacent
Re:Glad they got things back up (Score:5, Informative)
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Exactly. The FIRST time you sync a new generator to the grid, that can get a little hairy, because you've got to get the phases checked to make sure their rotation matches with the phase rotation on the rest of the grid. But once you've got phase match, with modern sync check relays and automatic syncing and switching it's pretty routine.
Now...back in the day, before modern digital relays, when you had to watch a rotating needle on a dial and the three blinking lights, and the sync check relay was an el
Hurricane preparedness test. (Score:2)
Dear God where are the facts? (Score:5, Informative)
This is what it was SUPPOSED to do! (Score:5, Informative)
These plants were designed to shut down in case of a fall in the power reaching them from *other sources* (because they need, e.g., to run cooling pumps for a safe shutdown and can't count on their own power). I'm not sure why the outside power browned out, but it did, so these plants did what they were designed to do.
Re:This is what it was SUPPOSED to do! (Score:4, Insightful)
All sorts of things could do this (Score:5, Informative)
What would it take to trigger the automatic release of the control rods? An earth tremor above a pre-set limit, insufficient input of cooling water from rivers (or water that's too hot or too impure), a controller hitting the wrong switch, a software glitch, a glitch in a clock crystal screwing with timing calculations, a loose connector, a chip in an old-style spring-based socket catapulting itself into the air (which they had a nasty habit of doing), erronious control signals from other power stations, a downed power line on any segment with single points of failure, etc.
Of these, the vast majority apply to any power station - one line down not too long ago caused a blackout that covered three States and half of Canada. One line down between the east and west coasts about 14-15 years ago shut down large parts of the northwest USA for a couple of weeks. Cascading failures are inherent in the meta-stable mashup of networks that form the power grid. Too many SPFs, too little redundancy, too many communication glitches, too few contingency plans.
Personally, I think the grid needs to be massively redesigned, with far better (and more intelligent) signalling, far more redundancy at all levels and a huge upgrade on software and hardware (NT4 and Windows 3.11 are not acceptable to me for mission-critical systems - they're tried and tested, but they're not reliable and they're not secure).
Of course, this won't happen, massive cascading faults will continue to be reported on a regular basis, and people will continue to be surprised when they occur. Preventative maintenance on the scale needed to cure the system as a system is so expensive (even though it's one-off), the distributed costs of regular blackouts on even a gigantic scale look cheaper on the balace sheet, so an inefficient, decrepid, flawed power grid becomes the preferred option.
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I was wondering what happened (Score:3, Interesting)
Not surprising... it's FPL, after all... (Score:2)
Arghh! Media Feeds Nuclear Power Panic! (Score:2)
Right at the end the article also mentions that two coal-burning plants shut down as well.
Same thing, so why the emphasis on the nuclear plants?
Five undersea cables! Five reactors! (Score:5, Funny)
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Nothing to see here...it was a ships anchor.... (Score:2)
Happens all the time....
There is a fleet of ships...ah.. trucks repairing these things round the clock.
Why the power plants shut down (Score:3, Informative)
Now, if something goes wrong somewhere down the lines, the power plant may not be able to get a good read of the phase. At that point, you just shut down the power plant, shut down the substations (so there isn't customer load on the lines), get the switching stations fixed, start the power plant up again in phase, and reconnect the customers. It's only if the switching stations are really destroyed that they'd actually run a power plant for local customers disconnected from the national grid, and they'd have to shut it down again in order to rejoin the grid.
What happened today is actually how it's supposed to work in case of an equipment failure: a regional blackout, some time to repair the malfunctioning equipment or swap in replacements, and then restoring power. When the grid doesn't handle the failure correctly, power lines melt down and power company manholes and buildings blow up and service isn't restored for days to some customers.
Re:Why the power plants shut down (Score:4, Informative)
ROLFLAMO Power into and out of the electrical grid is not by the phase of the generator. Power into and out of the grid is by the prime mover, eg throttle and nothing else. Once a plant is online, the throttle doesn't change the phase, just the power. (infinate grid calcultions) Matching phase while connected is not monitored as the electrical locks it to the grid. Power factor is controlled by the voltage regulator. Over voltage produces a leading power factor and under excited generators produce a lagging power pactor. Excitation is used for correcting power factor with some voltage regulation/correction.
Matching phase is only something you do just before closing the breaker and it is almost always closed slightly out of phase by about 5-10 degrees leading while advancing (running slightly fast) so it can connect with little bounce. After that, it's in phase, even if the prime mover is shut down. (reverse power protection should relay it out at this point to allow it to stop rotating)
Disclaimer, I am not a powerhouse operator, but I am the son of a retired one.
Argh! Quit the terrorism angle already! (Score:5, Insightful)
1998: "A massive power outage left millions of people without power Friday. The cause of the blackout is unclear."
2008: "A massive power outage left millions of people without power Friday. The government says terrorism was not involved, but the cause of the blackout is unclear."
Sigh . . .
It's not Nuke's fault! (Score:4, Informative)
Overtaxed power system? (Score:3, Informative)
According to various reports, the outage began with equipment failure and the loss of a distribution substation. Unlike major transmission links, distribution substations feed local loads and are not a part of the transmission system critical to the movement of power between alternate sources. The loss of a distribution system results only in the loss of loads, not generating or transmission capacity.
Two things may have happened here. Neither bode well for the system's condition.
It is possible that, following a fault at the distribution substation, the primary protection relays failed to operate. There are (or should be) backup relays. But these typically take longer to operate and allow the fault transient to push the system into an unstable condition. This is bad design. System stability should be maintained even if one station's protection fails.
It is also possible that, in spite of the proper design of primary and backup protection, the regional grid is being run too to its stability limits. A fault condition properly considered in the system design which should not have caused stability problems did so because the system was being run beyond prescribed limits.
Both of these possibilities suggest that, in spite of the big midwest outage we had several years ago, lessons have not been learned.
I'm from Florida and have no power or internet (Score:5, Funny)
Re:I'm from Florida and have no power or internet (Score:5, Funny)
Vaporware (Score:5, Funny)
Firstly:
Where are the numbers on latency and bandwidth?
Details like this are frequently brushed aside when making unrealistic promises. Let's stop listening to the marketing department and talk to the engineers working specifically with IP over Carrier Pidgeon and IP over Avian Carrier in general. (From here on referred to as IPoAC) We have no hard numbers on packet size limits.
Secondly:
What is the average delay on DNS resolution?
Another salient fact glossed over is that IPoAC completely depends on DNS caches as name lookups are expensive. As well as how long does it take to train new carriers til they are able to follow the new routes?
These and other questions lead me to believe that IPoAC is entirely VAPOR and has most likely not even been successfully implemented in the real world.
Does anyone have any real stats we can use to examine this? Or is IPoAC just going to be rammed down our throats by another mega-corporation with an agenda? It's time to really open the discussion on IPoAC.
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African or European pidgeon?
Re:Vaporware (Score:4, Informative)
Sorry to burst your belief bubble... [linux.no]
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Idiot. No, not strong enough. Epic thinking fail.
Re:global warming (Score:4, Funny)
Re:global warming (Score:4, Funny)
Comment removed (Score:5, Funny)
Re:global warming (Score:5, Funny)
Comment removed (Score:4, Funny)
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Re:global warming (Score:4, Informative)
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The real story is that a bunch of electrons were pulled-over by a cop in Waldo for going c in a 25mph zone.
http://www.city-data.com/forum/florida/5365-moved-waldo-florida-speed-trap.html [city-data.com]
Re:global warming (Score:4, Funny)
Re:global warming (Score:5, Informative)
Re:global warming (Score:5, Informative)
Re:global warming (Score:5, Informative)
Re:global warming (Score:5, Funny)
Oh
Re:global warming (Score:5, Informative)
A substation. Not the reactor. Then the reactor went offline because of the undervoltage condition caused by that power outage. Neutron-absorbers in the fuel had *nothing* to do with this.
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Neutron-absorbers have something to do with minimum down times for nuke plants.
I'd have to guess the reactors generators were over-voltage due to lack of load and that triggered the shutdown. I can't imagine they ran the reactors control systems off the Miami substation.
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Actually, nuclear plants ARE dependant on grid power for operations. It may seem odd that a plant generating many megawatts to a gigawatt of power needs an external supply, but it's a matter of safety. Were the plant to run exclusively on it's own power, a single malfunction could leave it in a state where it has no power for coolant pumps yet the reactor is at full power. So, if grid power to the plant drops, the reactor shuts down immediatly as a precaution.
The Chernobyl plant was carrying out an experi
Re:global warming (Score:5, Interesting)
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- and that's why we don't have regular interplanetary space flight
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I am not a nuclear engineer, so maybe I'm missing something obvious. That said, I don't understand why the system would automatically shut down due to a no load condition.
I understand why a backup generator for a house does this. It's to prevent linemen from getting killed touching lines that they assume are not hot while repairing a downed power line. One would not expect a lineman to assume a nuclear plant's output lines are not hot, however, so that reasoning doesn't apply.
I might be able to under
Re:global warming (Score:5, Informative)
You have to cool the steam down somehow, normally it looses energy by turning the generators but if that is not the case the energy needs to go somewhere.
The steam is normally re-condensed and then reused in a closed or semi closed loop depending on whether there are cooling towers. There is no way that the
cooling capacity would be able to dissipate the full load and hence the need to rapidly shut-down. This is the same for coal and gas plants as well.
Re:global warming (Score:5, Informative)
This is the key point that the idiot with the +5 mods above is missing.
This shutdown has nothing to do with neutron poisoning, and everything to do with load loss, the same as any conventional power plant. Negative reactivity from 135Xe typically doesn't prevent restart for an hour or so, and as the news is reporting the reactors are running again they must have had then back on line fairly quickly.
And yes, I am a nuclear physicist, and my undergraduate education as an engineer included reactor design.
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Re:global warming (Score:4, Informative)
http://www.nuceng.ca/ep6p3/class/Module3D_XenonJun21.pdf [nuceng.ca]
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LOL
Re:global warming (Score:4, Informative)
The Xenon is what prevents you from starting the reactor once the grid problem has been fixed. Thus while the reactors had nothing to do with the cause of the shutdown, they can't simply be restarted the moment the problem is gone, you have to wait for several hours or even a day. The time period depends a bit on the precise reactor type, and some can be safely restarted without waiting for Xenon to decay. I don't know about the specific reactors in question, so I can't tell if this was an issue or not.
Re:global warming (Score:5, Informative)
Fission products in the fuel have everything to do with why the plant was shut down. Operating nuclear plants run at a significant percentage of their capacity for reasons of economy. A sudden loss of load (as in the disconnect opening) results in the rapid rise in primary coolant temperature due to noplace for the energy to be dissipated. This will result in a reactor shutdown shortly after the load is lost (either by overtemperature or by turbine overspeed trip).
Heck, a sudden loss of turbine load can cause the turbine to overspeed, causing a turbine trip which in turn causes an automatic scram. Since every good discussion needs a car analogy, imagine driving up a steep hill and then knocking the transmission into neutral while keeping the accelerator mashed. RPM goes up, eh?
Even inserting control rods doesn't drop power fast enough to prevent heating up. After shutdown the fission products in the core continue to decay, releasing significant amounts of heat which must be dissipated.
That's what I love about slashdot... folks argue with experts without having a background to do so.
missed opportunity (Score:3, Insightful)
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Re:MOD PARENT UP (Score:5, Funny)
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And THIS is exactly how we will end up if we don't. Newsflash, buddy, but the nuclear plant had nothing to do with it other than "being there", the problem was in a distribution switch [youtube.com] that failed. These failures will happen no matter how many tree hugging hippies there are or are not, but I'm sure you won't let that stop you.
No, we will not run out of oil (Score:3, Informative)
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